Yeah sometimes the best replies I can make are "I'm sure if you wrote it people would be greatful". I don't like saying "no" to people, and often go out of my way to answer quite complicated questions.

But when receiving a brief "Point me at a tutorial for XXX/YY/ZZ" email it's hard to discern whether the person wants to learn, is incapable of using a search engine, or is really contacting the wrong person.